Flexible facing for pulleys



M. F. WILLIAMS.

FLEXIBLE FACING FOR PULLEYS. APPLICATION man ms. 21. 1920.

1,484,239., Patented new. 311, 1922.

coo

Fatented @ct. 3i, i922.

STATES Elisa-iii MILTON 3E. WILLIAMS, OF ST. LOUIS, MISSOURI, ASSIGNOR0F FORTY-NINE ONE- HUNDREDTHS T0 HAROLD M. PLAISTED, OF ST. LQUIS,-I1IISSOURI.

FLEXIBLE FACING For. PULLEYS.

Application filed February 27, 1920.

T 0 Mi whom it may concern Be it known that I, MILTON F. NrLLrAMs, acitizen of the United; States, residing at St. Louis, State of Missouri,have invented certain new and useful Improvements in Flexible F acingsfor Pulleys, of which the following is a specification.

This invention relates to certain new and useful improvements inflexible facings for pulleys, the peculiarities of which w1ll behereinafter described and claimed.

The main object of my invention is to provide a flexible facing withcross grooves which can be readily attached to an ordinary pulley andprovide side outlet passages for the air that is drawn in between thepulley and the belt. By doing away with the cushioning air the adhesionof the belt is increased with consequent increase of tractiveefficiency, regularity of angular velocity by avoidance of beltslippage, and reduction of wear on the belt.

In the accompanying drawing on which like reference letters indicatecorresponding parts, Fig. 1 represents a perspective view of a strip offlexible material with a series of slats mounted thereon, so as toprovide spaces between the slats; Fig. 2 a side view of a pulleyembodying my invention; Fig. 3 a face view of said pulley, partly insection on the line 2-2 of Fig. 2; Fig. 4 a perspective view of a stripof flexible sheet metal formed with cross grooves by bending the metal;Fig. 5 a similar view of my flexible facing with cross grooves cut inone face; Fig. 6 a side view of part of a pulley rim with the sheetfacing shown in Fig. 4 applied thereto; and Fig. 7 a sectional view ofFig. 6 on the line 7-7.

As is well known, the air cushion between a traveling belt and itspulley, prevents close adhesion of the belt and pulley face and resultsin slippage and consequent loss of power efliciency, and causes the beltto wear. My present improvements are designed to effect a change in theface of a pulley by means that can be readily applied without materialincrease of the diameter and will attain the objects stated above.Referring to the drawings, the letter A designates the rim of a pulleyof crown face or other style. which is to be provided with my improvedfacing. This facing consists of a flexible strip or backing B, that isprovided on its outer face with a series of cross Serial No. 361,809.

grooves a forming passages for the exit of the air drawn. in by theoncoming belt. In Fig. 1 these passages are formed by slats C riveted orotherwise secured to the flexible backing B, and separated a slightdistance as indicated inthe figure, so that when the facing is bentaround a pulley as shown in 1 1g. 2, the slats Wlll separate yet moreand form passages of comparatively slight width and suitable depthacross the face of the pulley, by which the air cushion finds exit at'the edge of the rim. This facing is riveted or otherwise secured to thepulley face as indicated in Fig. 5, and the relatively small width ofthe grooves 0 does not materially decrease from the contact surfacebetween the belt and the pulley, and such decrease is more than made upby the better contact of the belt with the pulley facing between thegrooves, on ac count of doing away with the cushioning air.

This flexible facing may likewise be formed of sheet metal as indicatedin Fig. 4 which may be bent, pressed, or otherwise formed withtransverse grooves, preferably as indicated in Fig. 4, and applied tothe face of a pulley as indicated in Figs. 6 and 7. In this sheet form ahollow space, cl, is left between the pulley face and the underside ofthe sheet material, and at the points where the sheet is riveted, awasher or filler piece D, Fig. 7, is provided to prevent the rivetpulling down the sheet material.

When a pulley is provided with a straight face, the flexible facing withits transverse grooves will be fastened thereto without change except aslight widening of the grooves in bending the flexible material to thecurve of the pulley, and the grooves will be substantially uniformthroughout their length.

When the ulley face is crowned however, the application of the flexiblefacing to the crown face of the pulley will cause a simi larcrowningeffect in the flexible facing, that will diminish the width ofthe cross grooves at the rim of the pulley on account of the slightlylessened diameter at the rim. On account of the flexible nature of thefacing and the more or less radial walls of the cross grooves, thisvariation in the width of the groove is effected as above stated, andthe flexible facing will likewise be crown face but the grooves will beof greater width at the center of the crowning thereby increasing thegrip of the belt upon the grooves.

InFig. is shown a form of my flexible facing in which the grooves arecut from a strip of material of sufficient thickness to I allow of suchgrooving on the outer face only, and such flexibility that it will bendin both directions around the pulley and across the pulley, when it is acrown pulley on which the facing is applied. In the sheet material formshown in Figs. 4: and

6, cross grooves are provided both above and below,that is, on the outerand the inner faces of the sheet or strip of material, but in Fig. 5 theouter face only is grooved.

In both styles, as well as that shown in Fig.

l, the grooves are slightly increased in width by the bending actlonproduced by applying the facing' to the pulley rim, and

are of maximum width in the center when applied to a'crown face pulley.

, J. desire to claim broadly this flexible facing fora pulley or similararticle to which it is adapted and do not limit'myself to the exactconstruction herein shown.

I claim 1. The combination with a pulley having a crown face, of aflexible facing having cross grooves,the said grooves being widest inthe crown center of the face and narrowed at theedge of the pulley rimby adjustment of said facing to the crowning of the pulley 2. As, a newarticle of manufacture a flexible pulley-facing having contlnuous' crossgrooves extending" from rim to rim on its relatively narrow and thesurface between said grooves being relatively-broad to provide belt,contact with minimum loss of bearing surface for the belt.

5. As a new article of manufacture, a flexible pulley facing comprisinga flexible backing and a series of slats transversely mounted on theouter face of said backing and adapted to separate and, form transversepassages between adjacent slats when said facing is bent around andsecured to a pulley, substantially as described.

In testimony whereof I have affixed my signature.

MILTON WILLIAMS.

